Re: Freelists

From: Tom Best <tombest_at_firstusa.com>
Date: 8 Aug 2001 05:40:52 -0700
Message-ID: <99ab87b0.0108080440.55a33a57@posting.google.com>

mickrice_at_techie.com (Mick Rice) wrote in message news:<645b6e08.0108080251.4b44c5d8_at_posting.google.com>...
> Ok, so when a transaction is inserting rows into a block it continues
> to do so until it hits PCTFREE. When rows are being deleted, at the
> point where the block is less that PCTUSED full the block is put back
> on the freelist for that table. My question is, when is the block
> initially taken off the freelist. If it's when we pass over the
> PCTUSED point how then do we continue to insert rows up to PCTFREE.
>
> Yours Expectantly,
>
> Mick Rice.

Mick:

You have to think of the fact that Oracle maintains a "state" of the data block. Meaning, it keeps track of whether it has hit PCTFREE or not. If it has, then it is in the mode of looking for PCTUSED to be hit, so it can then place it on the freelist.

Hope this helps.
Tom Best Received on Wed Aug 08 2001 - 07:40:52 CDT